Dog Days of Summer 2011 - Gallery VI

"I've noticed that people are coming out, eating in the tunnel more than usual," Salgrath said.

But it's a trend that doesn't gel with a revitalization plan for downtown Dallas. The Downtown Dallas 360 plan approved by the City Council calls for all shops and restaurants in the tunnels to relocate to the surface.

"As part of our overall approach to creating more storefront, ground-level retail, one of the things we're going to look at is the highest and best future use of the tunnels," said John Crawford, CEO of booster group Downtown Dallas Inc.

"There were places in the tunnels to go eat, and there weren't any other options," Crawford said. "That's not the case anymore."

But for some, it's going to take a lot to get them to say goodbye to the cool atmosphere below for the sunny, hot streets above.

"I'd like to see it improve more," Salgrath said.

Crawford said he will meet with a task force next month to discuss what's in store for the tunnels.